OBJECTIVES: Right heart catheterization is the gold standard for the diagnosis of pulmonary hypertension. However, echocardiography is frequently used to screen for this disease and monitor progression over time because it is noninvasive, widely available, and relatively inexpensive. The objective of our study was to perform a systematic review and quantitative meta-analysis to determine the correlation of pulmonary pressures obtained via echocardiography versus right heart catheterization and to determine the diagnostic accuracy of echocardiography for pulmonary hypertension.
METHODS: MEDLINE, EMBASE, PapersFirst, and the Cochrane collaboration and the Cochrane Register of controlled trials were searched and were inclusive as of February 2010. Studies were only included if a correlation coefficient or the absolute number of true-positive, false-negative, true-negative, and false-positive observations were available, and the “reference standards” were described clearly. Quality was assessed with the Quality Assessment for Diagnostic Accuracy Studies (QUADAS). A random effects model was used to obtain a summary correlation coefficient and the bivariate model for diagnostic meta-analysis was used to obtain summary sensitivity and specificity values.
RESULTS: Twenty-nine studies were included in the meta-analysis. The summary correlation coefficient between systolic pulmonary arterial pressure estimated from echocardiography versus measured by right heart catheterization was 0.70 (95% CI: 0.67-0.73) (n=27). The summary sensitivity and specificity for echocardiography for diagnosing pulmonary hypertension was 83% (95% CI: 73-90) and 72% (95% CI: 53-85) (n=12), respectively. The summary diagnostic odds ratio was 13 (95% CI: 5-31).
CONCLUSIONS: Echocardiography is a useful and noninvasive modality for measuring pulmonary pressures and for screening/diagnosing pulmonary hypertension.